全文获取类型
收费全文 | 3936篇 |
免费 | 319篇 |
国内免费 | 44篇 |
专业分类
耳鼻咽喉 | 106篇 |
儿科学 | 81篇 |
妇产科学 | 48篇 |
基础医学 | 674篇 |
口腔科学 | 72篇 |
临床医学 | 342篇 |
内科学 | 893篇 |
皮肤病学 | 65篇 |
神经病学 | 222篇 |
特种医学 | 215篇 |
外科学 | 608篇 |
综合类 | 166篇 |
一般理论 | 4篇 |
预防医学 | 154篇 |
眼科学 | 44篇 |
药学 | 218篇 |
中国医学 | 12篇 |
肿瘤学 | 375篇 |
出版年
2023年 | 25篇 |
2022年 | 59篇 |
2021年 | 124篇 |
2020年 | 74篇 |
2019年 | 81篇 |
2018年 | 95篇 |
2017年 | 89篇 |
2016年 | 85篇 |
2015年 | 89篇 |
2014年 | 132篇 |
2013年 | 140篇 |
2012年 | 197篇 |
2011年 | 219篇 |
2010年 | 135篇 |
2009年 | 164篇 |
2008年 | 187篇 |
2007年 | 212篇 |
2006年 | 195篇 |
2005年 | 176篇 |
2004年 | 180篇 |
2003年 | 146篇 |
2002年 | 109篇 |
2001年 | 117篇 |
2000年 | 87篇 |
1999年 | 104篇 |
1998年 | 73篇 |
1997年 | 68篇 |
1996年 | 53篇 |
1995年 | 59篇 |
1994年 | 34篇 |
1993年 | 30篇 |
1992年 | 67篇 |
1991年 | 62篇 |
1990年 | 63篇 |
1989年 | 73篇 |
1988年 | 68篇 |
1987年 | 57篇 |
1986年 | 42篇 |
1985年 | 48篇 |
1984年 | 22篇 |
1983年 | 20篇 |
1982年 | 26篇 |
1981年 | 19篇 |
1980年 | 22篇 |
1979年 | 15篇 |
1978年 | 24篇 |
1977年 | 20篇 |
1976年 | 27篇 |
1975年 | 12篇 |
1974年 | 13篇 |
排序方式: 共有4299条查询结果,搜索用时 31 毫秒
21.
Samuel C Leong 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2006,16(1):43-44
Cleaning a firearm can be a hazardous task even when the gun is not loaded. This is the first reported case of hand injury from the barrel bore cleaning brush. Early surgical exploration and washout of the wound is required as it often heavily contaminated with rust and grime. The cleaning agents used are also highly corrosive to tissue. 相似文献
22.
Polycystic kidney disease is an autosomal dominant disease that may be associated with cystic disease of the liver. In women, the cysts may develop early and be more troublesome than in men. Cystadenocarcinoma of the pancreas is uncommon, comprising 1% of primary pancreatic malignancies. This case report is the first to describe a familial association between polycystic kidney disease and cystadenocarcinoma of the pancreas and liver in the English medical literature. A patient with autosomal dominant polycystic kidney disease (ADPKD) and multiple hepatic cysts developed cystadenocarcinoma of the pancreas with multiple malignant liver cysts. The patient's mother, sister, and niece had ADPKD, and the patient's sister also died of pancreatic cystadenocarcinoma. We believe that the development of these two disease entities in which the primary pathology is cyst formation has a genetic association. (Gastroenterology 1997 Jun;112(6):2104-7) 相似文献
23.
Background : The results of management of seminoma of the testis at the Department of Radiation Oncology St Vincent's Hospital, Sydney were evaluated retrospectively to: (i) establish that outcomes were in keeping with published results from centres in Australia and overseas; (ii) assess the impact of chemotherapy on management; and (iii) to determine ‘best practice’ management protocols based on our results and a review of the relevant literature. Methods : (i) Assessment of treatment results for stage I and II seminoma of the testis treated by post-orchidectomy radiotherapy and/or chemotherapy at St Vincent's Hospital between 1979 and 1993; (ii) literature review of published data from Australian and overseas centres on the management of seminoma of the testis, and in particular the use of surveillance or chemotherapy either alone, at time of relapse or combined with radiotherapy; and (iii) development of recommendations for use as management protocols in our department. Results : Our data and a review of the literature suggest that post-orchidectomy radiotherapy with chemotherapy for relapse in stage I and IIA disease results in long-term cure rates approaching 100%. Treatment with chemotherapy either routinely or selectively or using a surveillance policy is unlikely to show any improvement in outcome and may be less cost-effective and/or produce increased morbidity and the risk of secondary leukaemia. For stage IIB disease (5–10 cm) the use of initial combination chemotherapy with or without subsequent radiotherapy did not appear to give better outcomes than initial radical radiotherapy alone, reserving chemotherapy or further radiotherapy for relapse. For bulkier stage IIB disease (> 10cm). the use of initial chemotherapy plus consolidation radiotherapy appeared to be an appropriate treatment. Conclusions : Management protocols for seminoma of the testis at St Vincent's Hospital, Sydney Department of Radiation Oncology currently are (i) stage I, IA and IIB (5–10 cm): post-orchidectomy radiotherapy alone with chemotherapy or further radiotherapy for relapse; and (ii) stage IIB (> 10 cm) disease: initial chemotherapy post-orchidectomy followed by radiotherapy to sites of initial disease involvement. 相似文献
24.
Jongkolnee Settakorn Anthony S Y Leong 《Applied immunohistochemistry & molecular morphology》2004,12(3):198-204
Subclinical or latent cases of gluten-sensitive enteropathy (GSE) are difficult to diagnose, and serology-positive, histology-negative (minimal morphologic change) and serology-negative, histology-positive patients have been identified. Both, particularly the histology-negative group, require the correct diagnosis for proper management, especially because the concept of minimal histologic change GSE has escaped attention in standard textbooks. We assessed the numbers and distribution of intraepithelial T cells and their subsets with CD3, CD8, and CD4 immunostaining and examined for crypt hyperplasia with mitotic and Ki-67 proliferative indices with the aim of refining the criteria for the diagnosis of minimal change GSE. Duodenal biopsies from 46 clinically suspected cases of GSE tested for antigliadin, antiendomysium, and antitissue transglutaminase antibodies were divided into four groups: serology-positive, histology-positive (S+H+, n = 20); serology-positive, histology-negative (S+H-, n = 22), representing the minimal morphologic change group; serology-negative, histology-positive (S-H+, n = 4); and serology-negative, histology-negative (S-H-, n = 28), controls with histologically normal duodenal biopsies obtained for unrelated reasons. The numbers of CD3+ and CD8+ intraepithelial T cells (IETCs) were significantly higher in histology-positive biopsies with (mean, 40.3/100 and 39.3/100 enterocytes, respectively) and without positive serology (mean, 33.3/100 and 35/100 enterocytes, respectively) compared with all other groups (S+H-, mean, 26.5/100 and 24.3/100 enterocytes, respectively; S-H-, mean, 23.3/100 and 17.9/100 enterocytes, respectively). Values for Ki-67 index in crypt enterocytes were also significantly different between histology-positive and histology-negative groups (P = 0.000). The distribution of CD3+ and CD8+ IETCs was mostly even along the surface enterocytes in histology-positive cases compared with the controls, which showed an uneven distribution. The 2 parameters that significantly discriminated between minimal morphologic change GSE (S+H-) and controls (S-H-) were Ki-67 index (P = 0.007) and the distribution pattern of CD8+ IETCs (P = 0.049). CD4 IETC counts were generally low, with no significant difference between all groups. The few S-H+ cases seen most likely represented false-negative serology, because the assessed parameters of this group and S+H+ cases were indistinguishable. 相似文献
25.
Pheochromocytoma and paraganglioma: comparison of MR imaging with CT and I-131 MIBG scintigraphy 总被引:6,自引:0,他引:6
To ascertain the magnetic resonance (MR) imaging characteristics of pheochromocytomas and paragangliomas and to compare MR with computed tomography (CT) and iodine-131 metaiodobenzylguanidine (I-131 MIBG), 19 patients (18 with pheochromocytomas, one with a paraganglioma) were studied. The 18 patients with pheochromocytomas had had positive findings with I-131 MIBG scintigraphy. Abdominal pheochromocytomas were generally hypointense compared with normal liver on T1-weighted MR images and extremely hyperintense on T2-weighted MR images. MR imaging was preferable to CT in the evaluation of primary pheochromocytomas due to superior tissue characterization, particularly in the patient with hypertension and borderline catecholamine levels. For patients with recurrent or metastatic disease, the data suggest that I-131 MIBG scintigraphy is the examination of choice. 相似文献
26.
Evaluation of a new enzyme-linked immunosorbent assay test for rotavirus antigen in faeces 总被引:6,自引:0,他引:6
下载免费PDF全文
![点击此处可从《Journal of clinical pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
A new commercial test for the diagnosis of rotavirus gastroenteritis was assessed. With some modifications it compared favourably with electron microscopy and immunofluorescence. 相似文献
27.
Identification and purification of a recombinant Treponema pallidum basic membrane protein antigen expressed in Escherichia coli. 总被引:5,自引:11,他引:5
下载免费PDF全文
![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
W S Dallas P H Ray J Leong C D Benedict L V Stamm P J Bassford Jr 《Infection and immunity》1987,55(5):1106-1115
A recombinant plasmid designated pLVS3 previously was described that harbored a 14-kilobase insert of Treponema pallidum genomic DNA. Escherichia coli maxicells programmed with this plasmid synthesized three treponemal protein antigens of molecular weights 39,000, 35,000, and 25,000 (39K, 35K, and 25K proteins, respectively). In this study, a detailed deletion analysis of pLVS3 demonstrated that the genetic information for all three protein antigens is contained within a 1.5-kilobase EcoRI-HpaI restriction fragment. The DNA sequence of this fragment revealed a single open reading frame of 361 codons that most likely encodes a signal peptide-bearing precursor to the 39K protein that can be transiently detected in E. coli maxicells. Evidence indicated that the 35K and 25K protein antigens are derivatives of the larger protein and are only produced in maxicells. A significant elevation in expression of the 39K treponemal protein antigen in E. coli was obtained by using the E. coli lpp and lac promoters and a genetic construction in which the signal peptide and first four residues of the "mature" 39K protein were replaced by six amino acids encoded by the vector. This hybrid protein exhibited an unusually high pI, which greatly facilitated its purification to homogeneity. By using antibody prepared against the hybrid protein, the native treponemal protein counterpart, also of molecular weight 39,000, was identified as a membrane component of T. pallidum. Since the native protein also exhibited a net positive charge, it has been designated the T. pallidum basic membrane protein. 相似文献
28.
Oncogenesis is the consequence of a series of genetic alterations that allow unrestrained cellular growth, tissue invasion, and eventual metastases. Tumor-related genes can be classified into functional categories. Proto-oncogenes/oncogenes have a stimulatory role in cell growth, and the inactivation of cancer-suppressor genes/antioncogenes results in the loss of cell cycle regulation. More recently, three other groups of tumor-related genes have been recognized. They include the antiapoptosis genes which protect from programmed cell death, the antimetastasis genes, and multidrug resistance genes. Besides aiding in tumor diagnosis, the detection of such tumor-associated genes and their products allows the identification of individuals with an inherited predisposition to neoplastic growths, and the overexpression of many of these oncogene products has been shown to be a potential marker of tumor behavior and a predictor of treatment outcome and response. The ability to utilize DNA and RNA probes for nucleic acid hybridization and polymerase chain reaction procedures in cell and tissue preparations of solid tumors and lymphoid proliferations expands and complements the information provided by immunohistochemical techniques. These probes allow direct visualization and correlation of specific genes and their protein products with cytomorphologic features, and form a powerful addition to the armamentarium of the cytopathologist and surgical pathologist. © 1995 Wiley-Liss, Inc. 相似文献
29.
30.
Cells are known to be surrounded by nanoscale topography in their natural extracellular environment. The cell behavior, including morphology, proliferation, and motility of bovine pulmonary artery smooth muscle cells (SMC) were studied on poly(methyl methacrylate) (PMMA) and poly(dimethylsiloxane) (PDMS) surfaces comprising nanopatterned gratings with 350 nm linewidth, 700 nm pitch, and 350 nm depth. More than 90% of the cells aligned to the gratings, and were significantly elongated compared to the SMC cultured on non-patterned surfaces. The nuclei were also elongated and aligned. Proliferation of the cells was significantly reduced on the nanopatterned surfaces. The polarization of microtubule organizing centers (MTOC), which are associated with cell migration, of SMC cultured on nanopatterned surfaces showed a preference towards the axis of cell alignment in an in vitro wound healing assay. In contrast, the MTOC of SMC on non-patterned surfaces preferentially polarized towards the wound edge. It is proposed that this nanoimprinting technology will provide a valuable platform for studies in cell-substrate interactions and for development of medical devices with nanoscale features. 相似文献